What happens if you’re on the move and your cell phone runs out of batteries? For most people, it means waiting until you can access your charger. But scientists at Virginia Tech at Blacksburg[3] have developed a new kinetic charger that makes juicing up your phone as easy as shaking your hand.

The built-in charger works on the principle of piezoelectricity[4] – every time you tap the screen or move your phone around, the charger harvests energy that can be used to run your device during an emergency[5]. While the technology isn’t strong enough to run your phone continuously, it could generate enough power for emergency use.

Shashank Priya[6] and his colleagues experimented with zinc oxide to develop the technology. The piezoelectric charger could be mounted in a cell phone underneath the keys or screen, where it would convert mechanical vibrations into electricity. It’s an exciting development that could provide cell phone users with an emergency source of power that might not be available otherwise.